Process and products therefrom



Patented Mar. 6, 1945 UNITED STATES PATENT orncs PROCESS AND PRODUCTS THEREFROM James Emory- Kirby, Wilmington, Del., assignor to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware No Drawing. Application September 17, 1941, Serial No. 411,261

11 Claims. (CI- 18-54) This invention relates to colored shaped objects from cellulose derivatives and particularly to films and threads.

The coloring of shaped objects from cellulose derivative presents certain problems relating to the fastness of the color and the uniformity or levelness of the color obtained. In particular, wash fastness of textiles, especially of viscose rayons, is a problem. Rayons in general can be dyed with the same type of dyestuffs as those used on cotton, but the greater amnity for the dyestuif and the lower wet strength of the rayon considerable. Leuco bases have also been used as viscose modifiers, but such a process leaves no choice of color once the yarn is spun.

This invention has as an object the provision'of a process for obtaining dyeings of cellulosic shaped objects of unusual fastness and uniformity. A further object is to provide a procedure for obtaining dyeings on rayons of unusual wash fastness and levelness without recourse to severe processing conditions and with a minimum of handling on the part of the dyer. Another ob- ,ject comprises shaped objects capable of receiving different colorings or dyeings. Other objects will appear hereinafter.

These objects are accomplished by the following invention wherein a condensation product of a maleic anhydride-olefln interpolymer with an aromatic amine, said condensation product being capable of reacting with a diazonium compound and having on the aromatic nucleus 9. hydrqxyl group, or a primary, secondary or tertiary amino group or having reactive methylene groups, is dispersed in a solution of a cellulose derivative, the cellulosic material is regenerated from the solution, intimately associated and interspersed with said condensation product, in a suitable solid form and the shaped object thus produced is treated with an aqueous solution of a diazonium compound to produce an azo dye within the cellulosic material.

cellulose benzoate or mixed-esters, such as cellulose acetate-butyrate. Esters of inorganic acid may also be used, e. g., cellulose sulfate. It may also be applied to cellulose ethers, e. g., ethyl- I cellulose, methylcellulose, benzylcellulose, alka- 19 commercial viscose 1-5% (based on the cellulose) li soluble glycolcellulose and celluloseglycollic acid. I

In the preferred mode of operation of the process of this invention, there is added to standard of the condensation product of the maleic anhydride-olefln interpolymer containing at least six recurring aromatic nuclei bearing amino or hydroxyl groups or at least six recurring methylene 16 groups capable of reacting with a diazonium salt.

The addition of the modifying agent to the viscose may be accomplished either in the mixer during the dissolution of the cellulose xanthate in dilute alkali solution or by simply stirring into 20 the viscose at any time prior to the regeneration of the cellulose. Thismodified viscose is ripened in the usual manner and is then spun into threads or cast into films by following the methods well known to the art. Thus, if a continuous filament yarn is to be made, the modified visthrough a spinneret into a coagulating bath comcose containing, for example, 7% cellulose and 6% alkali and 2% (based on the cellulose) of a.

polymeric dye coupling intermediate is allowed to ripen to a salt index of 3-5 and is forced prising, for example, 9-l1% sulfuric acid, 19-23% sodium sulfate, 0-4% glucose, and 054.0% zinc sulfate. It is immaterial whether spinning is by the bobbin or pot process, but the examplesbe-- low illustrate the use of the invention in the bobbin process. The thread may be of total denier varying from 50 to upwards of 200 denier with individual filaments ranging from 1-20 deniers. Other spinning conditions may include,

for example, a bath travel of 20-200 inches, bath temperature of -65" 0., a tension on the gel thread of 0.1-1.0 g./d., and a threadspeed of 2500-5000 inches per minute. However, insofar as they eflect the realization of the central fea- 45 tures of this invention, these conditions are not critical and are stated here merely to'illustrate the ranges in which commercial yarns may be produced. If staple fibers are spun, the spinning procedure is similar to the above except that the number of 'holes in the spinneret is increased The cellulose derivative is one which can bebrought into solution. In a particularly useful and important phase of the present invention which is described in detail below, the cellulose derivative is cellulose xanthate, but the invention is also applicable to cellulose esters of organic acids, e. g. cellulose acetate, cellulose propionate,

greatly and the bath composition, spinning tension, spinning speed, temperature, etc., are adjusted in accordance with known principles in order to produce good fiber properties. If film 5 is .produced, the modified. viscose is extruded through a slit into a coagulating bath such as one containing 10-13% sulfuric acid and 18-25% sodium sulfate. The regenerated cellulose structure, whether fiber or film, is washed free of acid,

dcsulfuredby treating with a dilute alkaline solution such as 0.2 to 0.3% sodium carbonate, so-

dium sulfide, orother rayon purification salt, and, if desired, is bleached before drying. These steps are optional, however, and are not fundaamine in diluteacid with sodium nitrite, or by dissolving a stabilized diazonium salt in water.

The polymeric compounds useful as addition agents in this invention contain aromatic nuclei or methylene groups capable of coupling with diazonium salts. These aromatic nuclei or meth ylene groups are present as side groups attached through amide linkages to an interpolymer formed from maleic anhydride and an olefin.

The diazo bases which are usedin the formation 'of the diazonium compounds for coupling with the polymeric modifying agents to form azo dyes in the cellulose structure include any aromatic or heterocyclic primary amine capable of forming a diazonium salt and reacting with substituted aromatic or reactive methylene groups. The choice of particular polymeric dye coupling intermediate and of diazonium salt will, of course, depend on the color of the dye ultimately desired. However, in the case of the polymericdye coupling intermediate, a single compound added in the viscose usually can give rise to a range of dyes simply by varying the character of the diazonium salt reacted with' it. By way of illustrating this point further, there are given below Table I tabulating a number of polymeric compounds, and Table II tabulating a number of azo dye coupling residues and diazo bases suitable for use in this invention together with the colors of the resulting dyestuffs.

TABLE I Typical polymeric materials Styrene-maleic anhydride interpolymers condensed with aromatic, amino compounds, e. g

Ethylene-'maleic anhydride interpolymers condensed with aromatic amino compounds. e. g--- 'Propylene-maleic anhydride in.-"

terpolymer condensed with aro matic-amino compounds, e. g H-acid Butylene-maleic anhydride inter- I polymers condensed with aromatic amino compounds, e. g

The fiolymerlc materials of this invention thus have the structure sponding'to an olefin the double bond or which is replaced by a single bond, 1. e., a saturated link- Aminophenol J-acid As; above TABLE 11 Color of the dye Amine condensed Diezo base formed Aminophenol Aniline Yellow.

d-nitraniline Yellow-orange. Naphthylaminesulionic Orange.

ac l-(m-aminophenyD-3- S-aminobenzenesulfonic Yellow. {nethyl-B-pyrazoacid.

4-nitraniiine Yellow-orange. o-Anisidine Orange Para-aminoacetoamt- 34minobenzenesulfon1c Yellow anllide. acid.

i-nitraniline Yellow-orange. o-iinisidinon- Orange. Jacid (2-amino-fi Aminobenzenedisul- Goldenyellow.

naghtholJ-sulfonic ionic acid. J a

7-metboxy-8-amino-3- Cerise. v naghtbalenesulfonie ac l-amino-fi-naphtbelene Scarlet.

sulfonlc d. o'Dianhidine Purple. 7-metboxy-8-amino-3- Blue-green.

na btlialenesnli'onic I ac d azo-meta-benzenesulfonic acid. H-acid (l-amino-S- 2,4-dichloroanilihe Yellow-orange.

naphtbol-iLti-disulionic acid.

l-amino-S-naphthalene- Red. sulfonic acid. cDianisidine Blue.

N-aminophenox 3-emlnohenzenesulfonlc- Yellow-orange.

ethyl M-acid iacid(alkaline). amino-fi-iga phtbol- 7-sulionic d). y

1,5-aminonaphthalene- Bed. suil'onioacid (alkaline).

z-diehloroaniline )Cerise. (acid). 2 I o-Dianlsidine (acid Purple. 2-ehloro-4-nitran line Blue.

a d). 2. nitroaniline (acid). Blue-green. N-beta-aminoethyl amminobenzenesullonic Yellow-orange. J acid. acid (alkalineh v l-amino-li-napbthalene- Red.

sullonic acid (alkaline). f 2-chloro-4-nitroaniline .Magenta.

(acid). g

age, between two carbons from which stem the two valences of the divalent radical, i. e. R is the corresponding to the alkylene or olefine, and X is a monovalent residue capableef coupling'with a 1 l'vicinal a ylener including substituted alkylene this invention are prepared vary with the" type give an azo dye. In the R is CHa-CHa-, in

diazonium compound to case of ethylene polymer the case of styrene To be capable of coupling with a diazonium compound to ing:

A. An 'tached thereto, an activating group such as a hydroxyl group or a primary, secondary or tertiary amino group, together with a reactive position," 1. e., a position ortho or para to (separated by an even number, from two to four, ofnuclear carbons from) said hydroxyl or amino group, which is either free or occupied by agroup which is removed during the coupling reaction.

B. A radical containing at least one active methylene group. By the term active methylene group is meant herein a methylene group capable of coupling with a diazonium compound. Examples of such active methylene groups are those of the beta-dik'etones such as bis-acetoacetbenzidide and of the pyrazolones such as l-phenyl-3-methyl-5-pyrazolone.

Examples of the colors obtainable with maleic anhydride-olefin condensation products of various amines coupled with various diazo bases, i. e., bases which are transformed into the corresponding"diazor iium salt are given in the following table.

give a dye, X must be one of the follow- Tne methods. by which polymers. suitable for of polymericmaterial used. No claim is made to aromatic nucleus bearing, directly atthe novelty of these polymers and the basic polymers are generally well described in the patent and chemical literature. For example, methods suitable to the preparation of styrene-maleic anhydride interpolymers may be found in U. S. Patent 1,976,679 and U. S. Patent 2,047,398. By way of illustration there is outlined .below a general method (Example A) for effecting condensation of an aminonaphtholsulfonic acid with a styrene-maleic anhydride interpolymer. This method may be used with such amino sulfonic acids as J-acid (2-amino-5-naphthol-7-sulfonlc acid), M-acid (1-amino-5-naphthol-7-sulfonic acid), R-acid '(2-amino-8-naphthol-6-sulfonic acid), and S-acid (l-amino-a-naphtholi-sulfonic acid) EXAMPLE A In a reaction vessel equipped with thermometer,

sealed stirrer and short fractionating column there are placed 240 parts of aminonaphtholsulfonic acid and 1,000 parts of dimethylformamide. These are stirred and heated to parts of water are added. Heat is then applied until distillation starts. A slow distillation is maintained until the temperature at the head of the column reaches 147-149 C. at which point there is added to thevessel a 'solution of one molecular equivalent of the polymeric anhydride 202 parts of styrene-maleic anhydride, 126 parts of ethylene-maleic anhydride, etc.), in 200parts of dimethylformamide. Heating is continued unn1 a total of 800 parts or solvent have been removed and the total heating time elapsed is six hours. The reaction mass is cooled to 60 C. and diluted with 4,000 parts of acetone while being agitated. A solid precipitate isremoved and dried to give a total recovery of about 95%. This material may then either be dialyzed in an alkaline solution to remove unreacted dye intermediate or it may be dissolved and added directly. to the solution of the fiber-forming material.

The foregoing is a general reaction and may be applied to aminonaphtholdisulfonic acids in which case 320 parts of the intermediate is used and 80 parts of sodium hydroxide added. Intermediates suitable for use in this reaction include H-A acid (1-amino-5-naphthol-3,6-disulfonic acid), K acid (1-amino-8-naphthol-4,6-disulfonic-acid), 2R acid (2-amino-8-naphthol-3,6-

comprising 11% sulfuric acid, 23% sodium sulfate, and 0.85% zinc sulfate. Temperature of the coagulating bath is 45 C., the bath travel 25 inches, and the spinning tension 20 g. for 150 denier thread. The thread is collected on a bobbin at a linear speed'of 2500 inches per minute and the collected yarn is washedfree of acid, desulfured by treating with a 0.3% sodium carbonate solution at 80 for minutes, and is again thoroughly Washed and dried. The yarn at this stage is colorless but can be dyed various colors by treating with solutions of diazonium salts. 'Thus, a golden yellow color is obtainedv by treating the yarn in the cold (ll-.5 C.) with a freshly prepared solution of diazotized metaanilinesulfonic acid of pH about 6-8. If Laurents acid (1-amino-5-naphthalenesulfonic acid) is used, a red color is obtained and if 80 C. when 40 parts of sodium hydroxide in 40 Y disulfonic acid), and 2S acid (I-amino-B-naph- 1 thol-2,4-disulfonic acid).

In another method theamino dye intermediate may be dissolved in an alkaline aqueous or dioxane-water solution and an equal molar amount of the olefin-maleic anhydride polymer added. The mixture is stirred at ordinary temperature for 24 hours while being kept at a pH EXAMPLE I To .a commercial viscose containing 7% cellulose and 6% alkali there is added 1.4%, based on the cellulose. of a styrene-maleic acid interpoly-mer containing J-acid residues attached through amide linkages, The viscose is ripened to a salt index of 4.2 and forced through a 40- hole spinneret into an acid-salt coagulating bath product with J-acid is prepared by the general method above outlined and. has the probable structural formula:

-CH-CHrCH -CH cHs C 01H C ONH s 03H The a: in the structural formula of this and subsequent polymer represents the number of units in the polymer, is an integer and .is at least six. It is usually even larger.

ly fast .to washing. The levelness of the shades obtained is also good.

EXAMPLE II soul . Yarn is spun by extruding this viscose into a coagulating bath comprising 9% sulfuric acid, 19% sodium sulfate, 4% glucose, and 0.85% zinc sulfate. The other spinning conditions, such as temperature of the bath, bath travel, tension, etc., are the same as in Example I. The washed and purified yarn is dyed a beautiful yelloworange. by treatment with a cold diazotized solution of 3-aminobenzenesulfonic acid at a pH of about 7. Some other colors which can be 0b- Th dyed yarns pr'ek pared by the above procedure have excellent physical properties, and the colors are extreme- '--OHa-CHr-CH--OH 1 Y a... iMG H is prepared with acetone'as solvent.

7 completely soluble in the acetone solution,

tained compounds are: red by treatment with Laments acid at pH of about 6 (1-amino-5-naphthalenesulfonic acid) and magenta. by treatment with 2-chloro-4-nitroaniline at pH of about 4-6. These'dyeings, like those of Example I, are fast to washing and level in shade.

EXAMPLE III Viscose of low alkali content such as one containing 7% cellulose and 4%alkali is modified by adding to it 2% of a styrene-maleic anhydride interpolymer containing recurring residues of 1- (m-aminophenyl) 3-methyl-5-pyrazolone attached through amide groups. This polymer is prepared by stirring an aqueous 10% solution of the above pyrazolone with an equal molar proportion of the styrene-maleic anhydride polymer for 24 hours at 20 to 5 0 C.. while 20% sodium hydroxide is added to keep the solution mildly alkaline (pH 7-9). The polymeric compound thus produced contains the following probable recurring units:

5H: 02H ONE N--N O=L\ CH: C s This viscose is spun into staple fibers by extrudin through a spinneret containing regenerating bath comprising 8.5% sulfuric acid, 24% sodium sulfate, and 0.7% zinc sulfate. The large bundle or rope of fibers so produced is purified and cut into staple lengths of 1.5 inches. These fibers can be spun into yarn using either the cotton or woolen system and the yarns dyed by treating with appropriate diazonium salts in solution. A solution of diazotized meta-aminobe'nzene-sulfonic acid gives a beautiful yellow color while diazotized para-nitraniline produces an orange.

' Exeurna IV 0 cm-co-on.

This viscose, when treated as in Example III, gives Y fibers which are converted to bright yellow azo with diazotized anilines.

I as V A 15% solution of rayon grade cellulose acetate To this is added 2% (based on the celluloseacetate) of the styrene-maleic anhydride interpolymer containing J-aeid residues employed in Example 1. Though this particular dyes when treated the yentional manner by extruding into the top of a from this yarn by treatment with diazo cloudy composition can be spun either in the conhot tower or by the electrostatic method. By coupling the yarn with -nitroaniline, the polymer within the fibers gives a bright orangecolor. The dyeing is fast to washing. In much the same manner, fibers or films from other organic sol- 3600 holes into a vent-soluble cellulose derivatives can be dyed.

In the process of this invention any condensation' product, having hydroxyl or amino groups. on

nuclear carbon and coupling positions thereby activated, or having reactive methylene groups, of an aromatic amine with a maleic anhydrideolefin interpolymer may be employed. The nucleus thus condensed is capable of coupling with a diazonium salt.

Any cellulose derivative, insoluble, capable of solution without essential chemical change whether in organic solvents as in the case of cellulose acetate or in aqueous alkali as in the case of cellulose xanthate or in aqueous alkali with the. aid of low temperatures or dispersing agents or both. as in the case of certain low substituted cellulose ethers may be employed in the process of this invention. Evenv a watersoluble cellulose derivative, e. g., water-soluble methylcellulose, which can be subsequently made into a film or fiber, or coated on a support, can be used.

The dyed yarns produced as a result of this invention may be put to any use in which ordinary textile rayons are adaptable. Since the dyes consist of a large number of azo units connected through covalent bonds into long chains which are, in fact, an integral part of the fiber, the colors obtained are extremely fast -to washing and, be-

cause of this, the yarns are particularly useful in woven and knitted fabrics subjected to frequent launderings. A special use for these fibers is in 40 the manufacture of cross dyed fabric which can molar portions of an be produced by weaving together one or more of these special rayons with standard rayon, cotton, or other fibers and treating the fabric with a so-' lution of a diazonium salt. Still another use is a simplified method of printing rayon fabrics in which two or more diazonium compounds are applied to the fabric composed of yarns containing polymeric dye coupling intermediates.

While regenerated cellulose sheeting, unlike a textile fiber, is not required to undergolaundry treatment, and therefore the advantage of a fast dye of the azo type over the dyes now used (mostly direct dyes and vegetable dyes) is not as great as in the case of textiles, nevertheless, "a dyestufi firmly attached to a polymer incorporated in the sheet, according to this invention, positively avoids dimculties from bleeding of colors should the sheet come in contact with water'or moist surfaces. The methods of incorporating the dye intermediate inthe regenerated cellulose'sheet and afterwards forming the dyestuff are, of

preferably waterwithin the scope of the claims.

What is claimed is: u 1. Process which comprises bringing an aqueous solution of a diazonium salt in contact with acellulosic structure having interspersed and coprecipitated therein a high molecular weight condensation product of an aromatic amine with a maleic acid-olefin hydrocarbon interpolymer, said condensation product being reactive with diazonium compounds and having, in a side group attached through an amide linkage to the polymer, a coupling group selected from the class consisting of an active methylene group, an arcmatic nucleus having a reactive position sepa rated-by an even number, from two to four,.of nuclear carbon atomsfrom a hydroxyl group on nuclear carbon and an aromatic nucleus having a reactive position separated by an even number, from two to four, of nuclear carbon atoms from an amino group on nuclear carbon.

2. Process which comprises bringing an aqueous solution of a diazonium salt in contact with 5. Process which comprises regenerating a cellulosic material in shaped form from a solution,-

in an inert solvent, containing a cellulose derivative having a cellulose nucleus, said solution having dispersed therein a high molecular weight condensation product of an aromatic amine with a maleic acid-olefin hydrocarbon interpolymer, said condensation'product having, in a side group attached through an amide linkage to the polymer, a coupling group selected from the class consisting of an active methylene group, an aromatic nucleus having a reactive position separated by an even number, from two to four, of nuclear carbonatoms from a hydroxyl group on nuclear-carbon and an aromatic nucleus having a reactive position separated by an even number, from two to four, of nuclear carbon atoms from an amino group on nuclear carbon, and bringing the shaped articletnus formed in contact with an aqueous solution of a diazonium salt.

6. Process which comprises casting a film from a solution, in an inert solvent, containing a cela cellulosic filament having. interspersed and coprecipitated therein a high molecular weight condensation product of an aromatic amine with a maleic acid-olefin hydrocarbon interpolymer,

said condensation product being reactive with diazonium compounds and having, in a side group attached through an amide linkage to the polymer, a coupling group selected from the class consisting of an active methylene group, an aro- .matic nucleus having a. reactive position separated by an even number, from two to four, of nuclear carbon atoms from a hydroxyl group on nuclear carbon and an aromatic nucleus having a reactive position separated by an even number, from two to four, of nuclear carbon atoms from an amino group on nuclear carbon.

3. A cellulosic structure having intimately associated and interspersed therewith an azo dye condensation product of a diazonium salt with a high' molecular weight condensation product of an aromatic amine with a maleic acid-olefin hydrocarbon interpolymer, said condensation product having, in a side group attached through an amide linkage to the polymer, 9. coupling group selected from the class consisting of an active methylene group, an aromatic nucleus having a reactive position separated by an even number, from two to four, of nuclear carbon atoms from a hydroxylgroup on nuclear carbon and an arcmatic nucleus having a reactive position separated by an even number, from two to four, of nuclear carbon atoms from an amino group on nuclear carbon. I

4. A cellulosic filament having intimately associated and interspersed therewith an azo dye condensation product of a diazonium salt with a high molecular weight condensation product of an aromatic amine with a maleic acid-olefin hydrocarbon interpolymer, said condensation product having, in a side group attached through an amide linkage to the polymer, a coupling group selected from the class consisting of an active methylene group, an aromatic nucleus having a reactive position separated by an even number, from two to four, of nuclear-carbon atoms from a hydroxyl group on nuclear carbon and an arcmatic nucleus having a reactive .position separated by an even number, from two to four, of nuclear carbon atoms from an amino group on nuclear carbon.

lulose derivative having a cellulose nucleus, said solution having dispersed therein a high molecular weight condensation product of an aromatic amine with a maleic acid-olefin hydrocarbon interpolymer, said condensation product having, in a side group attached through an amide linkage to ,the polymer, a coupling group selected from the class consisting of an active methylene group, an aromatic nucleus having a reactive position separated by an even number, from two to four, of nuclear carbon atoms from a ydroxyl group on nuclear carbon and an aromatic nucleus having a reactive positionseparated by an even number, from two to rour, vof nuclear carbon atoms from an amino group on nuclear carbon,

and bringing the film thus formed in contact with an aqueous solution of a diazonium salt.

7. Process which comprises spinning a filament from a solution, in an inert solvent, containing a cellulose derivative having a cellulose nucleus, said solution having dispersed therein a high 'molecular weight condensation product of an aromatic amine with a maleic acid-olefin hydrocarbon interpolymer, said condensation product having, in a side group attached. through an amide linkage to the polymer, a coupling group selected from the class consisting of an active methylene group, an aromatic nucleus having a reactive position separated by an even number,

, from two to four, of nuclear carbon atoms from a hydroxyl group on nuclear carbon and an aromatic nucleus having a reactive position separated by an even number, from two to four, of

;nuclear carbon atoms from an aminogroup on nuclear carbon, and bringing the filament thus formed in contact with an aqueous solution of a diazonium salt.

8. A cellulosic filament having intimately associated and interspersed therewith an azo dye condensation product of a diazonium salt with a high molecular weight condensation product of J-acid with a maleic acid-styrene interpoly mer.

9. Process which comprises spinning a filament from a solution, in an inert solvent, containing a cellulose derivative having a cellulose nucleus,

said solution having dispersed therein a high molecular Weightcondensation product of J -acid with a maleic acid-styrene interpolymer and soclated and interspersed therewith an azo dye condensation product of a diazonium salt with e high molecular weisht condensation product or i-(m-aminophenyl) -8-methyl-5-pyrazoloua with a maleic acid-styrene interpolymer.

1:1. Process which comprises spinnin: amiament from a solution. in an inert solvent,'containinz a cellulose derivative having a cellulose nucleus,. said solution havlnfl dimmed therein a high molecular weight condensation product oi i-(m-eminophenyl) -3-methyl-5-pyrazolone with a. 'maleic acid-styrene interpolymer and brinsim the filament thus formedin contact with an aqueous solution of a diazonium salt. 

